This commentary was originally published by The Regulatory Review. Reprinted with permission.
The Trump administration recently repealed the U.S. Environmental Protection Agency’s 2009 endangerment finding—the scientific and legal determination that greenhouse gases threaten public health and welfare that has anchored federal climate regulation for nearly two decades. Environmental Protection Agency Administrator Lee Zeldin called the finding “the Holy Grail of federal regulatory overreach.” Within weeks, a coalition of more than 20 states filed suit in the U.S. Court of Appeals for the D.C. Circuit to reverse the repeal. The legal battle that follows will help define American environmental policy for a generation.
Brigham Daniels and I did not plan the timing of our new book, Lessons for a Warming Planet: A Vital History of US Environmental Law, to coincide with this particular legal conflict. But we could not have chosen a more clarifying moment for its release. The endangerment finding repeal is not an aberration—it is a recognizable recurrence in a history that stretches back centuries. Law has always been the primary engine of both environmental exploitation and protection in the United States.
Our book traces that contest across five eras, arguing that each is defined by a dominant legal current accompanied by countercurrents that often become the next era’s mainstream. The history of American environmental law, we argue, is largely a history of those countercurrents eventually cresting into legal waves—sometimes tidal waves. And the breadth of laws that have fueled and averted environmental harms goes well beyond the pollution control and resource conservation laws conventionally demarcated as “environmental law.” Understanding this history is essential to navigating the present.
The first era, which we call the Allocation Era, runs from precolonial North America through 1890. Its defining feature was the use of law to promote resource extraction—almost exclusively for the benefit of European settlers and, later, industrial interests. This occurred often on the backs of African slaves and almost always at the expense of Indigenous peoples and the natural environment. The common law rule of capture rewarded whatever European settler claimed resources first, creating powerful legal incentives for extraction that extended from wildlife to water, oil, and gas.
Federal land law subsidized railroads, incentivized homesteading, and extinguished Native American land claims under color of legal doctrine. Yet even this era of unconstrained exploitation harbored countercurrents: The creation of Yellowstone National Park in 1872—the world’s first national park—established a legal precedent for federal land preservation that foreshadowed the era that followed.
The closing of the frontier triggered the first major oscillation in environmental policy to the Progressive Era (1890–1920). The end of westward expansion removed the nation’s plausible deniability about the costs of unchecked resource use, and a diverse coalition of reformers—conservationists, suffragettes advocating “municipal housekeeping,” muckraking journalists, and urban public health advocates—pushed for government to rein in corporate excess. President Theodore Roosevelt’s conservation agenda produced an unprecedented expansion of federal public lands. Congress enacted the Rivers and Harbors Act, the Federal Meat Inspection Act, and the Migratory Bird Treaty, all intended to protect environmental interests.
We are candid about the Progressive Era’s contradictions: Conservation policy was often entangled with nativist ideology, and its benefits were frequently captured by white, affluent communities at the expense of others. But the era’s unprecedented legal innovations—administrative agencies, science-based standard-setting, legal protections for the public good—fundamentally changed public and private life in the US.
Next, the Modernization Era (1920–1960) saw conservation largely yield again to development. The New Deal brought transformative investment in infrastructure—dams, highways, public works—that generated jobs and economic growth while accelerating pollution and ecological degradation. Federal housing subsidies and the Interstate Highway System centered the automobile-dependent suburb at the core of the American Dream, a vision accessible mostly to white, non-Latine families. Zoning laws ostensibly enacted for public welfare hastened urban sprawl, pollution, and racial segregation. Yet even this era produced modest federal experiments in pollution regulation that, largely unnoticed at the time, laid the groundwork for the transformative decade to come.
The Environmental Era (1960–1980) is the book’s most dramatic period of legal change—what we call an avulsion, a sudden flood that reshapes the legal landscape entirely. Rachel Carson’s Silent Spring, the Cuyahoga River fire, the Santa Barbara oil spill, and the first Earth Day built a political coalition that produced an extraordinary cascade of federal legislation such as the Clean Air Act, the Clean Water Act, the National Environmental Policy Act, the Endangered Species Act, and the Comprehensive Environmental Response, Compensation and Liability Act, among others. The gains were real and measurable: dramatically cleaner air and water and hundreds of species pulled back from extinction. But the rapid pace of legislative innovation left deficiencies in implementation and enforcement that a powerful deregulatory backlash would later exploit.
That backlash defines our fifth and current era. The Contested Era (1980 to present) is characterized not by a dominant legal current but by turbulence—incremental advances and rollbacks, divided government, litigation as the primary battleground, and deepening partisan polarization. The Reagan Administration’s effort to defund environmental agencies set the pattern—both Trump Administrations have intensified it. The repeal of the endangerment finding may be the Contested Era’s starkest expression yet. But the era has also produced countercurrents: state climate coalitions, the Inflation Reduction Act’s unprecedented green investment, and the immediate multistate legal response to the endangerment finding repeal itself. Those countercurrents are, in our reading of history, precisely how the next era begins.
The central lesson we draw is not that history guarantees a satisfactory outcome—it does not. The Anthropocene may pose challenges genuinely unprecedented in their scale and urgency. But history does demonstrate, repeatedly, that transformational legal change is possible even when it seems improbable. Every major advance in American environmental protection grew out of unconventional legal thought, earlier failures, and overcoming seemingly insurmountable resistance. The advocates who filed suit within weeks of the endangerment finding’s repeal are themselves a countercurrent—one whose predecessors we trace across four centuries in this book.
We wrote Lessons for a Warming Planet because we believe the past is not merely a record of what has been done. It is a repository of what might yet be possible and a guide for those with the legal imagination to get there.